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  • 1.
    Anderberg, Arne A.
    et al.
    Stockholm University, Faculty of Science, Department of Botany.
    Eldenäs, Pia
    Laboratory for Molecular Systematics, Swedish Museum of Natural History.
    Bayer, Randall J.
    Australian National Herbarium, Centre for Plant Biodiversity Research.
    Englund, Markus
    Stockholm University, Faculty of Science, Department of Botany.
    Evolutionary relationships in the Asteraceae tribe Inuleae (incl. Plucheeae) evidenced by DNA sequences of ndhF; with notes on the systematic positions of some aberrant genera2005In: Organisms Diversity & Evolution, ISSN 1439-6092, E-ISSN 1618-1077, Vol. 5, no 2, p. 135-146Article in journal (Refereed)
    Abstract [en]

    The phylogenetic relationships between the tribes Inuleae sensu stricto and Plucheeae are investigated by analysis of sequence data from the cpDNA gene ndhF. The delimitation between the two tribes is elucidated, and the systematic positions of a number of genera associated with these groups, i.e. genera with either aberrant morphological characters or a debated systematic position, are clarified. Together, the Inuleae and Plucheeae form a monophyletic group in which the majority of genera of Inuleae s.str. form one clade, and all the taxa from the Plucheeae together with the genera Antiphiona, Calostephane, Geigeria, Ondetia, Pechuel-loeschea, Pegolettia, and Iphionopsis from Inuleae s.str. form another. Members of the Plucheeae are nested with genera of the Inuleae s.str., and support for the Plucheeae clade is weak. Consequently, the latter cannot be maintained and the two groups are treated as one tribe, Inuleae, with the two subtribes Inulinae and Plucheinae. The genera Asteriscus, Chrysophthalmum, Inula, Laggera, Pentanema, Pluchea, and Pulicaria are demonstrated to be non-monophyletic. Cratystylis and Iphionopsis are found to belong to the same clade as the taxa of the former Plucheeae. Caesulia is shown to be a close relative of Duhaldea and Blumea of the Inuleae-Inulinae. The genera Callilepis and Zoutpansbergia belong to the major clade of the family that includes the tribes Heliantheae sensu lato and Inuleae (incl. Plucheeae), but their exact position remains unresolved. The genus Gymnarrhena is not part of the Inuleae, but is either part of the unresolved basal complex of the paraphyletic Cichorioideae, or sister to the entire Asteroideae.

  • 2.
    Anderberg, Arne A.
    et al.
    Stockholm University, Faculty of Science, Department of Botany.
    Englund, Markus
    Stockholm University, Faculty of Science, Department of Botany.
    Beentje, Henk
    On the systematic position of Inula rungwensis2008In: Compositae Newsletter, ISSN 0284-8422, Vol. 46, p. 83-84Article in journal (Other academic)
    Abstract [en]

    The systematic position of Inula rungwensis Beentje is discussed. It is concluded that it is conspecific with Gerbera piloselloides (L.) Cass. of the tribe Mutisieae.

  • 3. Anderberg, Arne A.
    et al.
    Rydin, Catarina
    Stockholm University, Faculty of Science, Department of Botany.
    Källersjö, Mari
    Phylogenetic relationships in the order Ericales s.l.: analyses of molecular data from five genes from the plastid and mitochondrial genomes2002In: American Journal of Botany, ISSN 0002-9122, E-ISSN 1537-2197, Vol. 89, no 4, p. 677-687Article in journal (Refereed)
    Abstract [en]

    Phylogenetic interrelationships in the enlarged order Ericales were investigated by jackknife analysis of a combination of DNA sequences from the plastid genes rbcLndhFatpB, and the mitochondrial genes atp1 and matR. Several well‐supported groups were identified, but neither a combination of all gene sequences nor any one alone fully resolved the relationships between all major clades in Ericales. All investigated families except Theaceae were found to be monophyletic. Four families, Marcgraviaceae, Balsaminaceae, Pellicieraceae, and Tetrameristaceae form a monophyletic group that is the sister of the remaining families. On the next higher level, Fouquieriaceae and Polemoniaceae form a clade that is sister to the majority of families that form a group with eight supported clades between which the interrelationships are unresolved: Theaceae‐Ternstroemioideae with FicalhoaSladenia, and Pentaphylacaceae; Theaceae‐Theoideae; Ebenaceae and Lissocarpaceae; Symplocaceae; Maesaceae, Theophrastaceae, Primulaceae, and Myrsinaceae; Styracaceae and Diapensiaceae; Lecythidaceae and Sapotaceae; Actinidiaceae, Roridulaceae, Sarraceniaceae, Clethraceae, Cyrillaceae, and Ericaceae.

  • 4.
    Anderberg, Arne
    et al.
    Stockholm University, Faculty of Science, Department of Botany.
    Manns, Ulrika
    Stockholm University, Faculty of Science, Department of Botany.
    Källersjö, Mari
    Phylogeny and floral evolution of the Lysimachieae (Ericales, Myrsinaceae): evidence from ndhF sequence data.2007In: Willdenowia, ISSN 0511-9618, E-ISSN 1868-6397, Vol. 37, p. 407-421Article in journal (Refereed)
    Abstract [en]

    Earlier hypotheses of floral evolution in Lysimachia and related genera were tested by phylogenetic analysis of DNA sequences from the plastid gene ndhF. It is concluded that taxa with flowers provided with oil-producing trichomes are not advanced and buzz-polinated species with anther cone are not ancestral as earlier proposed. Instead, species of Lysimachia with buzz-pollinated flowers belong to one derived clade, species with flowers provided with nectar producing trichomes belong to another, both groups have evolved from yellow flowered oil-producing ancestors. We also show that Lysimachia and most of its subgenera as well as the genera Anagallis, Pelletiera and Asterolinon are paraphyletic or polyphyletic as presently circumscribed, and that Trientalis and a few American species of Lysimachia are the closest relatives of the other species of Lysimachia + Anagallis, Asterolinon, Pelleriera and Glaux. The subgeneric classification and the biogeographical patterns are briefly discussed.

  • 5. Antonelli, A
    et al.
    Nylander, Johan
    Stockholm University, Faculty of Science, Department of Botany.
    Persson, C
    Sanmartín, I
    Tracing the impact of the Andean uplift on Neotropical plant evolution: evidence from the coffee family2009In: Proceedings of the National Academy of Sciences of the United States of America, ISSN 0027-8424, E-ISSN 1091-6490, Vol. 106, no 24, p. 9749-9754Article in journal (Refereed)
    Abstract [en]

    Recent phylogenetic studies have revealed the major role played by the uplift of the Andes in the extraordinary diversification of the Neotropical flora. These studies, however, have typically considered the Andean uplift as a single, time-limited event fostering the evolution of highland elements. This contrasts with geological reconstructions indicating that the uplift occurred in discrete periods from west to east and that it affected different regions at different times. We introduce an approach for integrating Andean tectonics with biogeographic reconstructions of Neotropical plants, using the coffee family (Rubiaceae) as a model group. The distribution of this family spans highland and montane habitats as well as tropical lowlands of Central and South America, thus offering a unique opportunity to study the influence of the Andean uplift on the entire Neotropical flora. Our results suggest that the Rubiaceae originated in the Paleotropics and used the boreotropical connection to reach South America. The biogeographic patterns found corroborate the existence of a long-lasting dispersal barrier between the Northern and Central Andes, the "Western Andean Portal.'' The uplift of the Eastern Cordillera ended this barrier, allowing dispersal of boreotropical lineages to the South, but gave rise to a huge wetland system ("Lake Pebas'') in western Amazonia that prevented in situ speciation and floristic dispersal between the Andes and Amazonia for at least 6 million years. Here, we provide evidence of these events in plants

  • 6. Bengtson, Annika
    et al.
    Englund, Markus
    Stockholm University, Faculty of Science, Department of Ecology, Environment and Plant Sciences. Swedish Museum of Natural History, Sweden.
    Pruski, John F.
    Anderberg, Arne A.
    Phylogeny of the Athroismeae (Asteraceae), with a new circumscription of the tribe2017In: Taxon, ISSN 0040-0262, E-ISSN 1996-8175, Vol. 66, no 2, p. 408-420Article in journal (Refereed)
    Abstract [en]

    Athroismeae is a small tribe of the Asteraceae-Asteroideae, the members of which show considerable variation in morphology. A molecular phylogenetic study of the tribe is presented for the first time, based on plastid (ndhF, trnH-psbA, trnL-trnF) and nuclear data (ETS, ITS). The phylogenetic relationships between the different genera within Athroismeae are discussed, and in addition, three unispecific genera: Anisochaeta, Artemisiopsis and Symphyllocarpus as well as Duhaldea (Inula) stuhlmannii, all earlier placed in other tribes, are here shown to belong within Athroismeae. Symphyllocarpus is sister to Centipeda and the earlier Symphyllocarpinae includes Centipedinae in synonymy. Furthermore, Cardosoa and Philyrophyllum are found to be integrated within Anisopappus and their generic status cannot be maintained. An outline of an amended circumscription of the Athroismeae is presented, with three new combinations and a description of the new subtribe Lowryanthinae.

  • 7.
    Borg, Agneta Julia
    et al.
    Stockholm University, Faculty of Science, Department of Botany.
    McDade, Lucinda
    Schönenberger, Jürg
    Stockholm University, Faculty of Science, Department of Botany.
    Molecular phylogenetics and morphological evolution of Thunbergioideae (Acanthaceae)2008In: Taxon, Vol. 57, no 3, p. 811-822Article in journal (Refereed)
  • 8.
    Borg, Agneta Julia
    et al.
    Stockholm University, Faculty of Science, Department of Botany.
    Schönenberger, Jürg
    Department of Structural and Functional Botany, Faculty Centre of Biodiversity, University of Vienna.
    Phylogenetic relationships in Acanthaceae based on nuclear and chloroplast sequences with particular focus on the ThunbergioideaeManuscript (preprint) (Other academic)
    Abstract [en]

    Phylogenetic analyses using maximum parsimony and Bayesian inference of one nuclear (ETS) and three chloroplast DNA regions (rpl16, rps16, trnT-trnL) were used to infer detailed phylogenetic relationships within the tropical and subtropical subfamily Thunbergioideae and among major lineages of Acanthaceae. For the first time, sequencing of the monotypic genus Anomacanthus is reported and its position as sister to Mendoncia gains strong support. Relationships among South and Central American Mendoncia species are poorly resolved, most likely reflecting an earlier rapid radiation. The clade with Anomacanthus and Mendoncia is sister to the clade comprising Pseudocalyx and Thunbergia. Relationships within the larger genus Thunbergia are generally well resolved. Two species (Thunbergia heterochondros and T. colpifera) appear morphologically intermediate between Pseudocalyx and Thunbergia. We discuss evolutionary relationships, including unclear species boundaries revealed by the molecular data, in a morphological context. Relationships among and within the four genera shed light on the biogeographic history of the group. All four genera are represented in Africa, from where Mendoncia appears to have dispersed to South and Central America and subsequently diversified into a large number of closely related species. The geographic origin of Thunbergia is uncertain, and the data point to interesting biogeographical patterns in this genus.

  • 9.
    Bremer, Birgitta
    Stockholm University, Faculty of Science, Bergianska botaniska trädgården (tills m Kungl. Vet. Ak.). Department of Botany.
    Linnaeus’ sexual system and flowering plant phylogeny2007In: Nordic Journal of Botany, Vol. 25, p. 5-6Article in journal (Other academic)
    Abstract [sv]

    Carl Linnaeus brought order to the knowledge of plants and animals by arranging all known species in encyclopaedic

    works. He proposed a system of plants, the sexual system, based on the number and arrangement of male and female

    organs. His artificial sexual system has since long been replaced by ‘natural’ or phylogenetic systems but there has never

    been a comprehensive comparison of the sexual system with modern plant classification. The currently most often used

    classification of flowering plants is the APG-system. It is based on comprehensive phylogenies of flowering plants,

    reconstructed by analyses of DNA data. The APG-system covers all flowering plants which are classified in 453 families

    and these are classified in 45 orders. Most of the species were not known at time of Linnaeus. Families and orders in the

    APG-system are arranged in larger informal groups representing major branches in the flowering plant phylogenetic tree.

    Three such groups are the monocots, the rosids, and the asterids.

    I have examined all genera published in Species plantarum (1753) and classified them according to order and major

    groups in the APG-system. All classes except one, number 15 Tetradynamia, comprises groups of unrelated plants. Not

    surprisingly, the sexual system does not display what we know today about plant relationships. As is evident from this

    analysis, there is little correspondence between the sexual system and the APG-system. This does not mean that the sexual

    system has been useless or misleading. When it was introduced, it formed the basis for much intensified research and

    increased knowledge of plants.

  • 10.
    Bremer, Birgitta
    et al.
    Stockholm University, Faculty of Science, Bergianska botaniska trädgården (tills m Kungl. Vet. Ak.). Department of Botany.
    Bremer, Kåre
    Heidari, Nahid
    Erixon, Per
    Olmstead, Richard G
    Anderberg, Arne A
    Källersjö, Mari
    Barkhordarian, Edit
    Phylogenetics of asterids based on 3 coding and 3 non-coding chloroplast DNA markers and the utility of non-coding DNA at higher taxonomic levels.2002In: Mol Phylogenet Evol, ISSN 1055-7903, Vol. 24, no 2, p. 274-301Article in journal (Other academic)
  • 11.
    Bremer, Birgitta
    et al.
    Stockholm University, Faculty of Science, The Bergius Botanical Garden Museum. Stockholm University, Faculty of Science, Department of Botany.
    Eriksson, Torsten
    Stockholm University, Faculty of Science, The Bergius Botanical Garden Museum. Stockholm University, Faculty of Science, Department of Botany.
    Timetree of Rubiaceae - Phylogeny and dating the family, subfamilies and tribes2009In: International journal of plant sciences, ISSN 1058-5893, E-ISSN 1537-5315, Vol. 170, no 6, p. 766-793Article in journal (Refereed)
    Abstract [en]

    Rubiaceae are one of the largest families of plants, with ;13,000 species. In this study, we have estimated the phylogeny for 534Rubiaceae taxa from329 generawith up to five different chloroplast regions by Bayesian analysis. It resulted in a highly resolved tree with many strongly supported nodes. There is strong support for the three subfamilies (Cinchonoideae, Ixoroideae, Rubioideae) and most of the 44 included tribes. A scaled-down data set of 173 Rubiaceae taxawas usedwith a Bayesian approach to estimate divergence times for clades classified as tribes and subfamilies. Four fossils were used as minimum age priors, one inside each subfamily and one for Rubiaceae as a whole (Faramea-type pollen, Scyphiphora pollen, Cephalanthus pusillus fruits, and Paleorubiaceophyllum eocenicum leaves). The estimated lineage (stem) divergence time for Rubiaceae is 90.4Ma. The estimated lineage divergence times for the subfamilies are 84.4 (86.6)Ma for Rubioideae, 73.1Ma for Ixoroideae, and 73.1Ma for Cinchonoideae.The estimated lineage divergence times for the tribes vary between 86.6 and 14.2Ma. Classification, relationships, geographical distribution, and age estimates are presented and discussed for all tribes.

  • 12.
    Bremer, Birgitta
    et al.
    Stockholm University, Faculty of Science, Bergianska botaniska trädgården (tills m Kungl. Vet. Ak.). Department of Botany.
    Jansen, R K
    Oxelman, B
    Backlund, M
    Lantz, H
    Kim, K J
    More characters or more taxa for a robust phylogeny--case study from the coffee family (Rubiaceae).1999In: Syst Biol, ISSN 1063-5157, Vol. 48, no 3, p. 413-35Article in journal (Other academic)
  • 13. Bremer, Kare
    et al.
    Friis, Else Marie
    Bremer, Birgitta
    Stockholm University, Faculty of Science, Bergianska botaniska trädgården (tills m Kungl. Vet. Ak.). Department of Botany.
    Molecular phylogenetic dating of asterid flowering plants shows early Cretaceous diversification.2004In: Syst Biol, ISSN 1063-5157, Vol. 53, no 3, p. 496-505Article in journal (Other academic)
  • 14. Buerki, S
    et al.
    Forest, F
    Acevedo-Rodríguez, P
    Callmander, M. W.
    Nylander, Johan
    Stockholm University. Stockholm University, Faculty of Science, Department of Botany.
    Harrington, M
    Sanmartín, I
    Küpfer, P
    Alvarez, N
    Plastid and nuclear DNA markers reveal intricate relationships at subfamilial and tribal levels in the soapberry family (Sapindaceae)2009In: Molecular Phylogenetics and Evolution, ISSN 1055-7903, E-ISSN 1095-9513, Vol. 51, p. 238-258Article in journal (Refereed)
  • 15.
    Dahlkild, Åsa
    Stockholm University, Faculty of Science, Department of Botany.
    Phylogenetic and ecological studies in lichenology: including studies of both mycobiont and photobiont2006Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    In this thesis different aspects in lichens are investigated, namely, the phylogeny of mycobiont and photobiont, and ecology in the form of species richness of certain habitats of the Uppland province, Sweden.

    Analyses of ITS sequences of the lichenized fungi genus Roccella (Roccellaceae) provide an intrageneric topology of the genus with emphasis on the European, Mediterranean and Macaronesian species. One species, Roccella elisabethae Tehler, is described and a key to the Macaronesian and European species is provided. Sequences from five Roccella species are new. One significant result is that the Macaronesian species constitute a monophyletic group.

    Newly designed algal-specific primers were used to amplify the ribosomal ITS region from 25 photobiont specimens from five lichenized fungal species of the family Physciaceae (Lecanorales). Trebouxia impressa was present in all mycobionts except Anaptychia ciliaris, which instead was associated with Trebouxia arboricola. A phylogeny for the photobiont, T. impressa, was compared to a phylogeny of the corresponding mycobionts. The general similarity of the mycobiont and photobiont trees may indicate a coevolutionary history.

    The ribosomal SSU region and the rbcL gene were sequenced from total DNA extracts from thalli of 8 species of Siphula (Icmadophilaceae) and 6 species of Parasiphula (Coccotremataceae). All specimens were found to have Elliptochloris bilobata in a wider sense as photobiont, indicating independent accession of photobionts for the two mycobiont genera.

    The epiphytic lichen flora on Fraxinus exelcior and Acer platanoides in lanes and two types of wooded meadows were investigated in Uppland, Sweden. Altogether 129 lichen species were found, five of which are listed in the Swedish Red List of threatened species. The species richness was affected by substrate, habitat, and distance to dust source. Lanes had the highest species richness, and Fraxinus excelsior had higher species richness than Acer platanoides.

  • 16.
    Dehghani, Reihaneh
    Stockholm University, Faculty of Science, Department of Zoology.
    Aspects of carnivoran evolution in Africa2008Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    This thesis concerns the evolution of African small carnivorans, with emphasis on East African Viverridae and Herpestidae (Carnivora, Mammalia). Viverridae and Herpestidae are two Old World feliform (belonging to the cat branch) carnivoran families with a confusing, and sometimes even misleading, taxonomic and systematic history, in addition to a scarce fossil record.

    A new genus and species from Fort Ternan, western Kenya, dated to ca 14 Mya (million years ago), was described and tentatively assigned to the Viverridae. The excellent preservation of this material has the potential to shed much light on the evolution of feliform carnivorans from Africa. The fossil record of Carnivora from Laetoli, a Pliocene hominid-bearing site in northern Tanzania, was also described and placed in an evolutionary context. The age of the fossil fauna from Laetoli ranges from 4.3 Mya to 2.5 Mya. The fossil material from this site is remarkable for two reasons: it is extensive in both number of taxa represented and amount of fossil material, especially of small carnivorans, and it is fossilized and preserved under aeolian conditions. In addition to these paleontological studies, two studies concerning extant Viverridae and Herpestidae were conducted. First, the phylogeography of the white-tailed mongoose, Ichneumia albicauda, (Herpestidae), was examined, with the tentative conclusion that its origin is southern African. Second, the ecomorphology and biogeography of African and Eurasian Viverridae and Herpestidae was analysed in order to investigate if these features can be used to help assess their evolutionary history in the absence of fossils. The pattern that emerges in this study is that the species of Viverridae and Herpestidae do not generally overlap in ecomorphology where they overlap geographically, which indicates considerable competitive interactions between the families in both Africa and Eurasia.

  • 17.
    Englund, Markus
    Stockholm University, Faculty of Science, Department of Botany.
    Clade size is not always an appropriate measure of diversification2011In: Proceedings of the National Academy of Sciences of the United States of America, ISSN 0027-8424, E-ISSN 1091-6490, Vol. 108, no 17, p. E84-E84Article in journal (Refereed)
  • 18.
    Englund, Markus
    et al.
    Stockholm University, Faculty of Science, Department of Botany.
    Pornpongrungrueng, Pimwadee
    Systematic Botany, Institute of Biological Sciences, University of Aarhus.
    Gustafsson, Mats H. G.
    Systematic Botany, Institute of Biological Sciences, University of Aarhus.
    Anderberg, Arne A.
    Stockholm University, Faculty of Science, Department of Botany.
    Phylogenetic relationships and generic delimitation in Inuleae subtribe Inulinae (Asteraceae) based on ITS and cpDNA sequence data2009In: Cladistics, ISSN 0748-3007, E-ISSN 1096-0031, Vol. 25, no 4, p. 319-352Article in journal (Refereed)
    Abstract [en]

    Phylogenetic relationships in Inuleae subtribe Inulinae (Asteraceae) were investigated. DNA sequence data from three chloroplast regions (ndhF,trnL–F and psbA–trnH) and the nuclear ribosomal internal transcribed spacer (ITS) region were analysed separately and in combination using parsimony and Bayesian inference. A total of 163 ingroup taxa were included, of which 60 were sampled for all four markers. Conflicts between chloroplast and nuclear data were assessed using partitioned Bremer support (PBS). Rather than averaging PBS over several trees from constrained searches, individual trees were considered by evaluating PBS ranges. Criteria to be used in the detection of a significant conflict between data partitions are proposed. Three nodes in the total data tree were found to encompass significant conflict that could result from ancient hybridization. Neither of the large, heterogeneous and widespread genera Inula and Pulicaria is monophyletic. A monophyletic group ("the Inula complex") that comprises all species of Inula include also Telekia, Carpesium, Chrysophthalmum, Rhanteriopsis, Amblyocarpum, and Pentanema sensu stricto. Two species of Pentanema were found to be closer to Blumea (including Blumeopsis and Merrittia) and Caesulia. The monophyletic "Pulicaria complex" includes all taxa with heteromorphic pappus. Within this group, Francoeuria is distinct from Pulicaria and merits recognition as a separate genus.

  • 19.
    Envall, Ida
    et al.
    Stockholm University, Faculty of Science, Department of Zoology.
    Erséus, Christer
    Zoologiska institutionen, Göteborgs universitet.
    Gustavsson, Lena
    Avdelningen för evertebratzoologi, Naturhistoriska riksmuseet.
    Ultrastructural investigation of coelomocytes in representatives of Naidinae and Rhyacodrilinae (Annelida, Clitellata, Tubificidae)2008In: Journal of Morphology, Vol. 269, no 9, p. 1157-1167Article in journal (Refereed)
    Abstract [en]

    Various types of free-floating cells are found in the coelomic fluid of representatives of several annelid groups. The ultrastructure of these "coelomocytes," however, has been studied to a limited degree. In this study, we used a transmission electron microscope to investigate the coelomocytes in specimens of five species of Naidinae and three species of Rhyacodrilinae (all oligochaetous clitellates within the family Tubificidae). These were compared with each other and with previously described coelomocytes of representatives of other oligochaete taxa. Only one distinguishable coelomocyte type was found in the studied specimens: a round to oblong cell without pseudopodia or other appendages, primarily containing membrane-bound granules of varying electron density, a prominent network of rough endoplasmic reticulum, and free ribosomes. This type differs to a great extent from most of the previously described coelomocytes, but shows similarities to certain types found in members of Enchytraeidae and Megascolecidae. Although we noticed some variation, we did not find any ultrastructural characters in these cells obviously useful for phylogenetic studies within Tubificidae.

  • 20.
    Envall, Ida
    et al.
    Stockholm University, Faculty of Science, Department of Zoology.
    Gustavsson, Lena M.
    Swedish Museum of Natural History.
    Erséus, Christer
    University of Gothenburg.
    Naidine tree of life (Annelida, Clitellata, Naididae) revisited – a multigene approachManuscript (Other academic)
  • 21. Eriksson, Torsten
    et al.
    Lundberg, Magnus
    Stockholm University, Faculty of Science, Department of Botany.
    Östensson, Pia
    Töpel, Mats
    Sibbaldia – a molecular phylogenetic study of a polyphyletic genus in RosaceaeManuscript (preprint) (Other academic)
    Abstract [en]

    Using DNA sequence data from nuclear ribosomal ITS in combination with plastid trnLF spacer and trnL intron data we show that Sibbaldia is a polyphyletic assemblage. It falls into five separate clades of Potentilleae, three within Fragariinae, and two within Potentilla (Potentillinae sensu Soják). In the main, our phylogenetic results agree with the findings by Soják (2008) which were based on anther structure. Four of our sampled Sibbaldia species remain in Sibbaldia, one [adpressa] is classified in Sibbaldianthe, one species [perpusilloides] is considered to represent an undescribed genus in Fragariinae, one [micropetala] is nested within the Potentilla anserina clade, and four species belong in a basal clade of Potentilla. Sibbaldiopsis is very close to Sibbaldia, and its single species should be named Sibbaldiopsis retusa (O.F. Müller) T. Erikss. and M. Lundberg.

  • 22.
    Erséus, Christer
    et al.
    University of Gothenburg.
    Envall, Ida
    Stockholm University, Faculty of Science, Department of Zoology.
    Marchese, Mercedes
    Instituto Nacional de Limnología (CONICET-UNL), Ciudad Universitaria, Santa Fe, Argentina.
    Gustavsson, Lena M.
    Swedish Museum of Natural History.
    The systematic position of Opistocystidae (Annelida, Clitellata) revealed by DNA data2010In: Molecular Phylogenetics and Evolution, ISSN 1055-7903, E-ISSN 1095-9513, Vol. 54, no 1, p. 309-313Article in journal (Refereed)
    Abstract [en]

    Opistocystidae Cernosvitov, 1936 is a largely Neotropical oligochaete taxon containing seven species. its familial status has never been formally challenged, although possible close relationships with Naididae and Phreodrilidae have been noted. Mitochondrial 12S and 16S rDNA, and nuclear 18S rDNA, of a range of aquatic oligochaete taxa, including Trieminentia corderoi (Opistocystidae), were analysed by Bayesian inference. This showed that T. corderoi is a derived lineage within Naididae, closely related to Pristina and its monotypic subfamily Pristininae. Opistocystidae as a whole (with its three genera, Opistocysta, Trieminentia, and Crustipellis) is thus likely to be a group within Naididae.

  • 23.
    Espeland, Marianne
    et al.
    Stockholm University, Faculty of Science, Department of Zoology, Systematic Zoology.
    Johanson, Kjell Arne
    Entomology Department, Swedish Museum of Natural History.
    Hovmöller, Rasmus
    Entomology Department, Swedish Museum of Natural History.
    Early Xanthochorema (Trichoptera, Insecta) radiations in New Caledonia originated on ultrabasic rocks.2008In: Molecular Phylogenetics and Evolution, ISSN 1055-7903, E-ISSN 1095-9513, Vol. 48, no 3, p. 904-17Article in journal (Refereed)
    Abstract [en]

    The toxic and nutrient poor ultrabasic rock substrate covering one-third of New Caledonia greatly influenced on the biogeography and diversity of plants in the island. Studies on the effect of ultrabasic substrate on fauna are almost entirely absent. In this paper we examine whether the diversification of Trichoptera of the New Caledonian endemic genus Xanthochorema Kimmins, 1953 was related to the presence of ultrabasic substrate. The analysis is based on data from a phylogeny derived from DNA sequences of mitochondrial COX1, COX2 and 16S, and nuclear EF1a genes. The study of the relationships between ancestral species and substrate was carried out using dispersal-vicariance analysis and tracing the history of substrate association with ultrabasic and non-ultrabasic distributions representing the terminals in the fully resolved phylogenetic tree. Our results show that (1) the ancestor of all Xanthochorema species was present on ultrabasic substrate, (2) early speciation events were restricted to ultrabasic substrate, (3) younger ancestral species dispersed into non-ultrabasic substrates, and (4) late speciation events were restricted to non-ultrabasic substrate. These results correspond to the hypothesis that New Caledonia once was more extensively covered by ultrabasic rocks than at present.

  • 24.
    Ferm, Julia
    Stockholm University, Faculty of Science, Department of Ecology, Environment and Plant Sciences.
    Paraphyly of the Malagasy genus Carphalea (Rubiaceae, Rubioideae, Knoxieae) and its taxonomic implications2013Independent thesis Advanced level (degree of Master (Two Years)), 40 credits / 60 HE creditsStudent thesis
  • 25. Fior, Simone
    et al.
    Karis, Per Ola
    Stockholm University, Faculty of Science, Department of Botany.
    Phylogeny, evolution and systematics of Moehringia (Caryophyllaceae) as inferred from molecular and morphological data: a case of homology re-assessment2007In: Cladistics, Vol. 23, no 1, p. 1-11Article in journal (Refereed)
  • 26.
    Funk, Vicki A
    et al.
    Smithsonian Institution, Washington, DC, .
    Karis, Per Ola
    Stockholm University, Faculty of Science, Department of Botany.
    Heterolepis: an unplaced genus2009In: Systematics, evolution and biogeography of compositae / [ed] Vicki A Funk, Vienna: International Association for Plant Taxonomy, University of Vienna , 2009, p. 483-486Chapter in book (Other academic)
  • 27.
    Gehrke, Berit
    et al.
    University of Zurich, Institute for Systematic Botany.
    Bräuchler, Christian
    Department Biologie I, Systematische Botanik, LMU Munich.
    Romoleroux, Katia
    Herbario QCA, Pontificia Universidad Católica del Ecuador.
    Lundberg, Magnus
    Stockholm University, Faculty of Science, Department of Botany.
    Heubl, G
    Department Biologie I, Systematische Botanik, LMU Munich.
    Eriksson, Torsten
    Stockholm University, Faculty of Science, Department of Botany. Stockholm University, Faculty of Science, The Bergius Botanical Garden Museum.
    Molecular phylogenetics of Alchemilla, Aphanes and Lachemilla (Rosaceae) inferred from plastid and nuclear intron and spacer DNA sequences, with comments on generic classification2008In: Molecular Phylogenetics and Evolution, ISSN 1055-7903, E-ISSN 1095-9513, Vol. 47, p. 1030-1044Article in journal (Refereed)
    Abstract [en]

    Alchemilla (the lady’s mantles) is a well known but inconspicuous group in the Rosaceae, notable for its ornamental leaves and pharmaceutical properties. The systematics of Alchemilla has remained poorly understood, most likely due to confusion resulting from apomixis, polyploidisation and hybridisation, which are frequently observed in the group, and which have led to the description of a large number of (micro-) species. A molecular phylogeny of the genus, including all sections of Alchemilla and Lachemilla as well as five representatives of Aphanes, based on the analysis of the chloroplast trnL–trnF and the nuclear ITS regions is presented here. Gene phylogenies reconstructed from the nuclear and chloroplast sequence data were largely congruent. Limited conflict between the data partitions was observed with respect to a small number of taxa. This is likely to be the result of hybridisation/introgression or incomplete lineage sorting. Four distinct clades were resolved, corresponding to major geographical division and life forms: Eurasian Alchemilla, annual Aphanes, South American Lachemilla and African Alchemilla. We argue for a wider circumscription of the genus Alchemilla, including Lachemilla and Aphanes, based on the morphology and the phylogenetic relationships between the different clades.

  • 28.
    Gelang, Magnus
    Stockholm University, Faculty of Science, Department of Zoology.
    Babblers, Biogeography and Bayesian Reasoning2012Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    In this thesis, I try to proceed one step further towards an understanding of the biogeographic processes forming the distribution patterns of organisms that we see today. Babblers and warblers are diverse groups of passerines that are phylogenetically intermixed with other groups in the superfamily Sylvioidea.

    First, the gross phylogeny of the babblers and associated groups was estimated. Five major lineages of a well-supported monophyletic babbler radiation were recovered, and we proposed a new classification at family and subfamily level. Further, the genus Pnoepyga was excluded from Timaliidae, and we proposed the new family Pnoepygidae fam. nov.

    Second, the systematic position was investigated for the Albertine Rift taxon Hemitesia neumanni, which was found to be nested within the almost entirely Asian family Cettidae, and possible biogeographical scenarios were discussed. We concluded that the most plausible explanation involved late Miocene vicariance in combination with local extinctions.

    Third, the historical biogeography of a Leiothrichinae subclade, the Turdoides babblers and allies, was inferred. We concluded that the Middle East region probably played an important role in the early history of this clade, followed by local extinctions in this region.

    Fourth, a Bayesian method to reconstruct the historical biogeography under an event-based model was proposed, where the total biogeographic histories are sampled from its posterior probability distribution using Markov chains.

    In conclusion, I believe that, especially with more sophisticated methods available, we will see an increasing number of studies inferring biogeographic histories that lead to distribution patterns built up by a combination of dispersals and vicariance, but where these distributions have been extensively reshaped, or litterally demolished, by local extinctions. Therefore, my answer to the frequently asked question dispersal or vicariance? is both, but not the least: extinctions.

  • 29.
    Gelang, Magnus
    et al.
    Stockholm University, Faculty of Science, Department of Zoology.
    Bohlin, Alexis
    Bayesian inference of total biogeographic history under an event-based modelManuscript (preprint) (Other academic)
    Abstract [en]

     

    We propose a Bayesian approach to infer the historical biogeography under an event-based model, where the total biogeographic histories are sampled from its posterior probability distribution using Metropolis-coupled Markov chain Monte Carlo. Total histories are stochastically mapped on a phylogeny followed by invoking a biogeographical model, which defines the biogeographical events dispersal, vicariance, persistence and extinction. A hypothetic order of probabilities for these events to happen is applied in the priors of the analysis, where a stick-breaking process is used to pick variables from a flat Dirichlet distribution. In comparison to the two most commonly used methods, the proposed method delivers relatively similar reconstructions, albeit with some differences such as favouring extinctions more. These differences are linked to either the treatment of total histories, or to the fundamental statistical differences of the three approaches. In conculsion, this method favours extinctions more than the compared methods, but the main difference is more complex and is instead linked to the treatment of total histories.

  • 30.
    Gelang, Magnus
    et al.
    Stockholm University, Faculty of Science, Department of Zoology.
    Pasquet, Eric
    Cibois, Alice
    Alström, Per
    Ericson, Per
    Stockholm University, Faculty of Science, Department of Zoology.
    Ancestral ranges concealed by local extinctions: the historical biogeography of the African and Asian Turdoides babblers and allies (Aves: Passeriformes)Manuscript (preprint) (Other academic)
    Abstract [en]

    Aim

    To infer the historical biogeography of the genus Turdoides and allies, and to investigate the impact of the geological history of the Arabian Peninsula on the biogeographic interactions between Africa and Asia.

    Location

    Terrestrial Africa and Asia, with focus on the Middle East.

    Methods

    A five-loci molecular phylogeny was estimated by Bayesian inference and by maximum likelihood. Divergence times were approximated by Bayesian inference under a relaxed clock model, and non-parametrically by asmoothing algorithm between sister paths (PATHD8). Historical biogeography was reconstructed by maximum likelihood approach under the DEC-model, and by the parsimony-based Bayes-DIVA on the trees sampled from the target distribution from the Bayesian inference of the phylogeny.

    Results

    The clade comprising Turdoides and its close relatives originated in the end of the Miocene, and initially the Middle East region played an important role. The clade radiated into two subclades, one mainly distributed in Africa, and one distributed in southern Asia, the Middle East and northern and eastern Africa.

    Main conclusions

    We propose that local extinctions may have played a key role, in combination with dispersals and vicariance, in forming the present distribution pattern of the study group. The Middle East has been an important and dynamic area for the early evolution of the investigated babblers. Further, we conclude that constraints on biogeographical inference have stronger impact on the analysis than does the biogeographical model implied in the analysis.

  • 31.
    Hallengren, Anders
    Stockholm University, Faculty of Humanities, Department of Literature and History of Ideas.
    Vivat Linnaeus! Mer blomster än ogräs i jubileets Linnérabatt: Även om systemet vittrat sönder lade Linné grunden för dagens botanik2007In: ANNEX: Recensionsbilaga till AXESS, ISSN 1651-0941, no 2 (Hösten 2007), p. sid. 4-8Article, review/survey (Other (popular science, discussion, etc.))
  • 32.
    Hovmöller, Rasmus
    Stockholm University, Faculty of Science, Department of Zoology.
    Molecular phylogenetics and taxonomic issues in dragonfly systematics (Insecta: Odonata)2006Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Dragonflies (Odonata) are one of the ancestral groups of extant insects. They represent one of the three most basal branches in the phylogeny of winged insects. The other two groups are the Ephemeroptera, mayflies, and Neoptera, the latter which covers the remaining winged insects. The first paper is about the phylogenetic position of Odonata in relation to the other basal insect clades using 18S and 28S rDNA sequences. It was demonstrated that there are under certain parameters a strong statistical support for a sister-group relationship between Odonata and Neoptera forming the group Palaeoptera. The second paper is about the phylogeny of the Holarctic dragonfly Leucorrhinia. Dragonfly larvae are frequently equipped with spines on the abdomen, with great variation in spinyness between species. From an analysis of sequences of ITS and 5.8S rDNA it was found that spines have been lost at least twice in Leucorrhinia, in the European L. rubicunda and again in a clade of North American species. The third paper is on the subfamily Ischnurinae (Odonata: Coenagrionidae), a group dominated by the two larger genera Ischnura and Enallagma along with several mono- or oligotypic genera. From the presented molecular study, using mitochondrial 16S rDNA and COII sequences, it is demonstrated that Ischnurinae, and Ischnura are monophyletic. Enallagma is not monophyletic, and the genus name Enallagma should be restricted to the E. cyathigerum clade. he fourth paper is a catalog of the genus Coenagrion, with full information on synonymy, type material and bibliographical data. The fifth paper is an appeal to the International Commission on Zoological Nomenclature to suppress the genus group name Agrion. The letter of appeal elucidates the priority of Agrion, and demonstrates why it has fallen out of use. A case if made for why Agrion should be placed on the list of unavailable names, and Calopteryx given full validity.

  • 33.
    Häggqvist, Sibylle
    Stockholm University, Faculty of Science, Department of Zoology. Naturhistoriska riksmuseet.
    Charting biodiversity: Scuttle flies and other poorly known insects in Sweden2016Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Biodiversity has fascinated people in all times. We as a species are part of the global ecosystem and our survival depends on many other species around us. Charting biodiversity, however, has proven more difficult than one could imagine. When Linnaeus and others started describing which species there are on Earth, people in general, and taxonomists in particular, could not imagine that we would not be finished 300 years later and even less that we would not be able to tell exactly how much there is left to describe.

    In this PhD thesis, I deal with relatively large organisms (compared to the average size of organisms left to be described), namely insects in general and scuttle flies in particular, within a limited and well-studied geographic region (Sweden). Nevertheless, the results show that we are far from completing the inventory for even this limited portion of global biodiversity. Since it was in Sweden that Linnaeus started his work and where he did most of it, the Swedish flora and fauna belong to the best known in the world. In spite of this, we show in paper I of this thesis that it is likely that a considerable portion of the Swedish insect fauna remains to be discovered. The white spots on the biodiversity map primarily concern small Diptera and Hymenoptera species that are decomposers or parasitoids. The scuttle flies (Diptera: Phoridae) are one of the insect families that contain more undescribed species than species known to science, both in Sweden and elsewhere. The situation is complicated by the fact that a large portion of the known scuttle-fly diversity is placed within a single genus, Megaselia, one of the most species-rich genera in the animal kingdom; almost 40 % of described phorids belong to this genus. Our lack of understanding of phylogenetic relationships within Megaselia has made taxonomic progress on the genus very difficult. In paper II, we define a new natural clade within Megaselia, the lucifrons group, based on both molecular and morphological evidence. We show that the group comprises at least three species in Sweden, one of which is described by us as new to science. In paper III, we present the first comprehensive molecular phylogeny of Megaselia. We identify 22 well-supported natural clades within the genus, comprising at least two species each. These clades are recognized as species groups; most of them have not been described previously. We identify eight additional, isolated single-species lineages, which may turn out to represent multi-species clades when molecular data become available for more species. The paper includes the description of 45 species new to science, all from Sweden. In paper IV, we revise the most basal of the 22 species groups, the spinigera group, and describe one additional new species to science from Sweden in this group. The thesis provides the first reasonably complete phylogenetic framework for Megaselia and its closest relatives, greatly facilitating further research into scuttle-fly diversity in Sweden and elsewhere.

  • 34.
    Häggqvist, Sibylle
    et al.
    Stockholm University, Faculty of Science, Department of Zoology. Swedish Museum of Natural History, Sweden.
    Ulefors, Sven Olof
    Ronquist, Fredrik
    Stockholm University, Faculty of Science, Department of Zoology.
    Phylogeny and species-group classification of the mega-diverse genus Megaselia (Diptera, Phoridae)Manuscript (preprint) (Other academic)
    Abstract [en]

    The genus Megaselia is one of the largest in the animal kingdom, with 1,600 described species and many more remaining to be discovered according to most experts. The biology is poorly known; some well-studied species have been shown to be parasitoids or extreme omnivores but it is suspected that larvae are mostly decomposers or fungivores. The genus can be found in most regions of the world but it is most diverse in the Holarctic, from temperate to arctic climates, at least judging from the described fauna. Work on Megaselia taxonomy is challenging due to the extreme species diversity, the poor knowledge of the higher-level phylogeny and the lack of molecular data. In this paper, we provide the first comprehensive study of Megaselia relationships based on molecular data. Although basal relationships in the genus remain uncertain, we identify 22 well-supported terminal clades, which we recognize as informal species groups. We briefly discuss the morphological characteristics of each species group, and the implications of our phylogenetic results for the genus-level classification of Megaselia and its closest relatives. We also provide molecular and brief morphological characterization of 45 Megaselia species new to science.

  • 35.
    Häggqvist, Sibylle
    et al.
    Stockholm University, Faculty of Science, Department of Zoology. Swedish Museum of Natural History, Sweden.
    Ulefors, Sven Olof
    Ronquist, Fredrik
    Stockholm University, Faculty of Science, Department of Zoology.
    The spinigera group of Megaselia (Diptera, Phoridae): molecular phylogeny, revision of the known Swedish fauna, and description of a new speciesManuscript (preprint) (Other academic)
    Abstract [en]

    With 1,600 described species, the scuttle-fly genus Megaselia is one of the largest genera of all organisms. A recent comprehensive molecular phylogenetic study suggests that most of the Megaselia species fall into a monophyletic group, the “core Megaselia clade”, leaving only two lineages outside: the spinigera group and the ruficornis group. Here, we focus on the spinigera group. We present a molecular analysis of its phylogenetic position within the subfamily Metopininae, and of relationships within it. The analysis is based on broader taxon sampling than in previous studies, covering additional lineages both within and outside the group. Our analysis supports the recognition of an “extended Megaselia clade” — including Myriophora, Pseudacteon, the M. ruficornis group and core Megaselia — and indicates that the spinigera group may be the sister group of this clade. Furthermore, our analysis shows that the spinigera group contains several species previously placed in Plastophora, Phalacrotophora or Kerophora, and we discuss the possibility of recognizing the spinigera group as a separate genus under one of those names. We also revise the known Swedish fauna of the group based primarily on study of material from Malaise traps, and show that the fauna includes a hitherto unknown species, which is described as M. proctoluteipes n. sp. Finally, we present a key to the known Swedish species.

  • 36. Ickert-Bond, Stefanie M.
    et al.
    Rydin, Catarina
    University of Munich, Germany.
    Renner, Susanne S.
    A fossil-calibrated relaxed clock for Ephedra indicates an Oligocene age for the divergence of Asian and New World clades and Miocene dispersal into South America2009In: Journal of Systematics and Evolution, ISSN 1674-4918, E-ISSN 1759-6831, Vol. 47, no 5, p. 444-456Article in journal (Refereed)
    Abstract [en]

    Ephedra comprises approximately 50 species, which are roughly equally distributed between the Old and New World deserts, but not in the intervening regions (amphitropical range). Great heterogeneity in the substitution rates of Gnetales (EphedraGnetum, and Welwitschia) has made it difficult to infer the ages of the major divergence events in Ephedra, such as the timing of the Beringian disjunction in the genus and the entry into South America. Here, we use data from as many Gnetales species and genes as available from GenBank and from a recent study to investigate the timing of the major divergence events. Because of the tradeoff between the amount of missing data and taxon/gene sampling, we reduced the initial matrix of 265 accessions and 12 loci to 95 accessions and 10 loci, and further to 42 species (and 7736 aligned nucleotides) to achieve stationary distributions in the Bayesian molecular clock runs. Results from a relaxed clock with an uncorrelated rates model and fossil‐based calibration reveal that New World species are monophyletic and diverged from their mostly Asian sister clade some 30 mya, fitting with many other Beringian disjunctions. The split between the single North American and the single South American clade occurred approximately 25 mya, well before the closure of the Panamanian Isthmus. Overall, the biogeographic history of Ephedra appears dominated by long‐distance dispersal, but finer‐scale studies are needed to test this hypothesis.

  • 37. Irestedt, Martin
    et al.
    Gelang, Magnus
    Stockholm University, Faculty of Science, Department of Zoology.
    Sangster, George
    Stockholm University, Faculty of Science, Department of Zoology.
    Olsson, Urban
    Ericson, Per
    Stockholm University, Faculty of Science, Department of Zoology.
    Alström, Per
    Neumann’s Warbler Hemitesia neumanni (Sylvioidea): the sole African member of a Palaeotropic Miocene avifauna2011In: Ibis, ISSN 0019-1019, E-ISSN 1474-919X, Vol. 153, no 1, p. 78-86Article in journal (Refereed)
    Abstract [en]

    We present molecular evidence that Neumann’s Warbler Hemitesia neumanni is deeply nested within the Cettiidae. The species’ distribution in the Albertine Rift of East Africa is intriguing, as the family Cettiidae is principally an Asian radiation. This disjunct distribution could be a result of colonization of Africa by long-distance dispersal, or the Cettiidae may at some point in the past have had a much larger geographical distribution that also covered parts of Africa.

  • 38.
    Jaeschke, Benedict
    Stockholm University, Faculty of Science, Department of Ecology, Environment and Plant Sciences.
    Exploring phenomena that affect the fate and impact of radioactive materials in the blue mussel2013Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Current protection of the marine environment from radiation is based largely on measuring, estimating and modelling accumulation and impact(s) of radionuclides in a few marine species. Using a relevant marine organism, this thesis focusses on investigating some poorly described phenomena that could cause deviations from predicted measurements.

    Paper I investigated the biological transformation of tritium (radioactive hydrogen) into an organic compound. The resulting organically bound tritium (OBT) showed increased accumulation in mussels, unique incorporation into a key biological molecule (DNA), extended persistence in tissues, and greater toxicity than the inorganic form. Paper II demonstrated significant disparity in OBT accumulation between functionally similar microalgae species and that OBT in algae is readily transferred to a consumer.

    Highly radioactive particles are a complex issue in radioecology due to their concentrated dose geometry, potentially inducing very different impacts in organisms, compared to external irradiation. Paper III developed a method to introduce radioactive particles that would facilitate their recovery, improve dose-calculation, and aid the measurement of toxicological endpoints. It also showed that such particles can be incorporated into mussel tissues, causing significant effects.

    In Paper IV, hypoxia – another major ecological hazard in the marine environment – was expected to reduce radiosensitivity. The minimal observable effect from radiation prevented identification of such an interaction, and indicates drawbacks in the (otherwise sensitive) endpoints used. It appears that stressors like hypoxia may be more of a health hazard to marine organisms than environmental levels of ionising radiation.

    By understanding such causes of variation in accumulation and impact, it is possible to improve risk assessment, providing more justification for regulations chosen and minimising conservatism in setting environmental standards.

  • 39.
    Jaeschke, Benedict C.
    et al.
    Stockholm University, Faculty of Science, Department of Systems Ecology.
    Bradshaw, Clare
    Stockholm University, Faculty of Science, Department of Systems Ecology.
    Bioaccumulation of tritiated water in phytoplankton and trophic transfer of organically bound tritium to the blue mussel, Mytilus edulis2013In: Journal of Environmental Radioactivity, ISSN 0265-931X, E-ISSN 1879-1700, Vol. 115, p. 28-33Article in journal (Refereed)
    Abstract [en]

    Large releases of tritium are currently permitted in coastal areas due to assumptions that it rapidly disperses in the water and has a low toxicity due to its low energy emissions. This paper presents a laboratory experiment developed to identify previously untested scenarios where tritium may concentrate or transfer in biota relevant to Baltic coastal communities. Phytoplankton populations of Dunaliella tertiolecta and Nodularia spumigena were exposed at different growth-stages, to tritiated water (HTO; 10 MBq l(-1)). Tritiated D. tertiolecta was then fed to mussels, Mytilus edulis, regularly over a period of three weeks. Activity concentrations of phytoplankton and various tissues from the mussel were determined. Both phytoplankton species transformed HTO into organically-bound tritium (OBT) in their tissues. D. tertiolecta accumulated significantly more tritium when allowed to grow exponentially in HTO than if it had already reached the stationary growth phase; both treatments accumulated significantly more than the corresponding treatments of N. spumigena. No effect of growth phase on bioaccumulation of tritium was detectable in N. spumigena following exposure. After mussels were given 3 feeds of tritiated D. tertiolecta, significant levels of tritium were detected in the tissues. Incorporation into most mussel tissues appeared to follow a linear relationship with number of tritiated phytoplankton feeds with no equilibrium, highlighting the potential for biomagnification. Different rates of incorporation in species from a similar functional group highlight the difficulties in using a 'representative' species for modelling the transfer and impact of tritium. Accumulations of organic tritium into the mussel tissues from tritiated-phytoplankton demonstrate an environmentally relevant transfer pathway of tritium even when water-concentrations are reduced, adding weight to the assertion that organically bound tritium acts as a persistent organic pollutant. The persistence, potential for biomagnification and the increased toxicity of organic tritium increases the potential impact on the environment following a release of HTO; current legislation does not adequately take into account the nature of organic forms of tritium and therefore may be underestimating accumulation and toxic effect of tritium in the environment. Such information is necessary to accurately assess the distribution of tritium following routine releases, and to adequately protect the environment and humans.

  • 40.
    Janz, Niklas
    Stockholm University, Faculty of Science, Department of Zoology.
    Ehrlich and Raven Revisited: Mechanisms Underlying Codiversification of Plants and Enemies2011In: Annual Review of Ecology, Evolution and Systematics, ISSN 1543-592X, E-ISSN 1545-2069, Vol. 42, p. 71-89Article, review/survey (Refereed)
    Abstract [en]

    After almost 50 years of scrutiny, the ideas that Ehrlich and Raven presented in their classical paper on the coevolution between butterflies and plants are still very much alive. Much of this interest has involved the potential for codiversification, both in how the interaction itself diversifies and how the interaction affects modes and rates of speciation. Despite high levels of conservatism and specialization, diversification of the interaction appears to be mainly a consequence of host shifts, but this somewhat paradoxical conclusion can be understood by an appreciation of the ecological as well as genetic mechanisms behind host shifts. There are several ways that the interaction can influence speciation, with or without host-plant-based di-vergent selection on reproductive barriers. One current debate is over the relative importance of radiations following shifts to new adaptive zones and elevated rates of speciation in groups with plastic and diverse host use.

  • 41.
    Janz, Niklas
    et al.
    Stockholm University, Faculty of Science, Department of Zoology. Stockholm University, Faculty of Humanities, Centre for the Study of Cultural Evolution. Ekologi.
    Nylin, Sören
    Stockholm University, Faculty of Science, Department of Zoology. Ekologi.
    The oscillation hypothesis of host-plant range and speciation2008In: Specialization, speciation and radiation: the evolutionary biology of herbivorous insects, Berkeley: University of California Press, 2008, p. 203-215Chapter in book (Refereed)
  • 42.
    Johanson, Kjell Arne
    et al.
    Stockholm University, Faculty of Science, Department of Zoology.
    Malm, Tobias
    Stockholm University, Faculty of Science, Department of Zoology, Systematic Zoology.
    Testing the monophyly of Calocidae (Insecta: Trichoptera) based on multiple molecular data2010In: Molecular Phylogenetics and Evolution, ISSN 1055-7903, E-ISSN 1095-9513, Vol. 54, p. 535-541Article in journal (Refereed)
    Abstract [en]

    Calocidae constitute a hypothesised monophyletic group of caddisflies (Trichoptera) being geographically restricted to New Zealand (one genus) and Australia (five genera). This analysis tests the monophyly of the family based on sequences from five different molecular genes. The complete data set includes 29 species and covers a complete genus representation of the Calocidae as well as representatives of other families in which one or more calocid genera have been classified. Sequences from two mitochondrial (cytochrome oxidase I and 16S) and three nuclear (elongation factor 1-a, RNA polymerase-II, and Cadherin) genes were used, resulting in a 3958 bp data set and 37.1% parsimony informative characters. The Cadherin (CAD) and RNA polymerase-II (POL-II) genes are used for the first time for revealing Trichoptera phylogenies. The character matrix was analyzed by using maximum parsimony (MP) and Bayesian criteria, the latter by applying three different partition strategies for comparison. Two most parsimonious trees were found, differing in the position of one clade within the sister-group to a monophyletic Calocidae. The Bayesian tree based on the maximum number of partitions differs from trees based on a reduced partition analysis with respect to taxa outside the current circumscription of Calocidae. Both the MP and Bayesian analyses left Calocidae monophyletic, with a monophyletic clade of all Australian genera being sister-group to the New Zealand genus. The results from the agreement subtree analysis demonstrates that CAD performs well both separately and in combination with other genes and adds substantial resolution to the calocid phylogeny in a combined MP analysis.

  • 43. Jønsson, Knud Andreas
    et al.
    Delhey, Kaspar
    Sangster, George
    Swedish Museum of Natural History, Sweden.
    Ericson, Per G. P.
    Irestedt, Martin
    The evolution of mimicry of friarbirds by orioles (Aves: Passeriformes) in Australo-Pacific archipelagos2016In: Proceedings of the Royal Society of London. Biological Sciences, ISSN 0962-8452, E-ISSN 1471-2954, Vol. 283, no 1833, article id 20160409Article in journal (Refereed)
    Abstract [en]

    Observations by Alfred Wallace and Jared Diamond of plumage similarities between co-occurring orioles (Oriolus) and friarbirds (Philemon) in the Malay archipelago led them to conclude that the former represent visual mimics of the latter. Here, we use molecular phylogenies and plumage reflectance measurements to test several key predictions of the mimicry hypothesis. We show that friarbirds originated before brown orioles, that the two groups did not co-speciate, although there is one plausible instance of co-speciation among species on the neighbouring Moluccan islands of Buru and Seram. Furthermore, we show that greater size disparity between model and mimic and a longer history of co-occurrence have resulted in a stronger plumage similarity (mimicry). This suggests that resemblance between orioles and friarbirds represents mimicry and that colonization of islands by brown orioles has been facilitated by their ability to mimic the aggressive friarbirds.

  • 44.
    Kainulainen, Kent
    Stockholm University, Faculty of Science, Department of Botany.
    Evolution and biodiversity of the Ixoroideae (Rubiaceae)2010Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    The phylogenetic relationships within subfamily Ixoroideae of the coffee family are investigated by phylogenetic reconstruction of molecular data, including regions of the chloroplast DNA (matK, ndhF, rbcL, rps16, trnH-psbA, trnS-G, and trnT-F), and the nuclear ribosomal DNA (ITS). The evolution of morphological characters within the group are inferred, with focus on characters used in classification. Ixoroideae have primarily been characterized by secondary pollen presentation, contorted corolla aestivation, and fleshy fruits. Secondary pollen presentation appears synapomorhic of a clade comprising the Ixoroideae crown group together with Retiniphyllum, whereas contorted corolla aestivation has evolved earlier and is synapomorphic for the crown group, Retiniphyllum, and Steenisia. Capsules likely represent a plesiomorphy from which various dry or fleshy indehiscent fruits have evolved independently in different clades. Reductions in seed number have also occured in many clades, none of which shows a secondary increase in the number of seeds.

    Within Ixoroideae, the phylogeny and tribal delimitations of Alberteae and Condamineeae are studied in more detail. The former appears restricted to Alberta, Nematostylis, and Razafimandimbisonia, a new genus described here. The Condamineeae are a diverse tribe largely unresolved in previous molecular phylogenetic studies. Our results support a synonymization of both Calycophylleae and Hippotideae, because these are nested within the Condamineeae. Ancestral state reconstructions indicate that intrapetiolar stipules, poricidal anthers, and protogyny, otherwise uncommon characters in Rubiaceae, all have evolved more than once in the Condamineeae.

    The rare genera Jackiopsis, Glionnetia, and Trailliaedoxa previously not included in molecular phylogenetic analyses, are all found nested within the Ixoroideae, and their systematic positions are discussed. The genera Bathysa, Calycophyllum, Elaeagia, and Rustia do not appear monophyletic. Consequently, resurrections of the names Holtonia, Schizocalyx, and Semaphyllanthe, and synonymizations of Phitopis (as Schizocalyx) and Tresanthera (as Rustia) are proposed. Also proposed are five new tribal names for clades that are not associated with any previously described tribes in the phylogenetic hypotheses presented.

  • 45.
    Kainulainen, Kent
    et al.
    Stockholm University, Faculty of Science, Department of Botany.
    Mouly, Arnaud
    Khodabandeh, Anbar
    Stockholm University, Faculty of Science, Department of Botany.
    Bremer, Birgitta
    Stockholm University, Faculty of Science, Department of Botany.
    Molecular phylogenetic analysis of the tribe Alberteae (Rubiaceae), with description of a new genus, Razafimandimbisonia2009In: Taxon, ISSN 0040-0262, E-ISSN 1996-8175, Vol. 58, no 3, p. 757-768Article in journal (Refereed)
    Abstract [en]

    The tribe Alberteae, presently classified in the subfamily Ixoroideae (Rubiaceae), has historically been an artificial grouping of genera. In the present study, phylogenetic analyses of the chloroplast DNA markers rbcL, ndhF, trnS-G, trnT-F and trnH-psbA as well as the ITS region of the nuclear ribosomal DNA, are done to assess the delimitation of Alberteae. The resulting phylogenetic hypothesis is highly resolved, with most clades strongly supported. The genus Alberta is found to be paraphyletic as presently circumscribed. As a consequence, we propose the new genus Razafimandimbisonia Kainul. & B. Bremer to accommodate the Malagasy species. The newly delimited Alberta is distinguished by having two calycophylls that expand after anthesis as well as awl-shaped stigma lobes. Razafimandimbisonia is distinguished from the remaining Alberteae by having dehiscent fruits and anthers without basal appendages. We demonstrate that the genera Airosperma, Boholia and Crossopteryx are not associated with Alberteae, as has previously been suggested. Alberteae is considered restricted to the genus Alberta endemic to Southeast Africa, and the two Malagasy endemic genera Nematostylis and Razafimandimbisonia.

  • 46.
    Kainulainen, Kent
    et al.
    Stockholm University, Faculty of Science, Department of Botany.
    Persson, Claes
    University of Gothenburg, Department of Systematic Botany.
    Eriksson, Torsten
    Swedish Museum of Natural History, Entomology Department.
    Bremer, Birgitta
    Stockholm University, Faculty of Science, Department of Botany.
    Molecular systematics and morphological character evolution of the Condamineeae (Rubiaceae)2010In: American Journal of Botany, ISSN 0002-9122, E-ISSN 1537-2197, Vol. 97, no 12, p. 1961-1981Article in journal (Refereed)
    Abstract [en]

    • Premise of the study: The Condamineeae have in previous molecular studies been shown to be part of an early-divergent cladewithin the subfamily Ixoroideae, together with the tribes Calycophylleae, and Hippotideae, and genera of the former Cinchoneae and Rondeletieae. Generic relationships within this clade have, however, remained largely unresolved

    .• Methods: In this study, the systematics of the Condamineeae was further examined by phylogenetic reconstruction of six cpDNA regions and one nrDNA region using parsimony and Bayesian Markov chain Monte Carlo inference. Morphological character evolution within the tribe was assessed by ancestral state reconstruction using likelihood optimization of characters onto Bayesian trees.

    • Key results: Calycophylleae appears polyphyletic. “Hippotideae” is monophyletic but nested within the Condamineeae. The phylogenetic hypotheses presented support a resurrection of the genera Holtonia, Schizocalyx, and Semaphyllanthe. Furthermore, Bathysa is found to be polyphyletic, Tresanthera is found nested within Rustia, and the taxonomically disputed genus Dialypetalanthus is here shown to be sister to a BothriosporaWittmackanthus clade. Morphological ancestral state reconstructions indicate that protogyny have evolved at least two times within the tribe and that indehiscent fruits, loculicidal fruit dehiscence, and intrapetiolar stipules have evolved independently several times. The occurrence of calycophylls (leaf-like calyx lobes), poricidal anthers, and winged seeds also appear homoplastic within the tribe.

    • Conclusions : A diagnosis and delimitation of the tribe Condamineeae is presented, with taxonomic proposals to synonymize Tresanthera and to transfer several species of Bathysa as well as Phitopis to a resurrected Schizocalyx.

  • 47.
    Kainulainen, Kent
    et al.
    Stockholm University, Faculty of Science, Department of Botany.
    Razafimandimbison, Sylvain
    Stockholm University, Faculty of Science, Department of Botany.
    Bremer, Birgitta
    Stockholm University, Faculty of Science, Department of Botany.
    Phylogeny and evolution of secondary pollen presentation, corolla aestivation patterns, fruit types, and seed number in the Ixoroideae (Rubiaceae)Manuscript (preprint) (Other academic)
    Abstract [en]

    Phylogenetic reconstructions using Bayesian and parsimony analyses of six chloroplast DNA region were performed in order to investigate character evolution and tribal relationships within the subfamily Ixoroideae (Rubiaceae). In the inferred phylogenetic hypotheses, the tribal relationships were mostly well supported, with the subfamily comprised of a crown group of two major sister clades termed the Coffeeae-alliance and Vanguerieae-alliance respectively, and a basal grade comprising Condamineeae, Henriquezieae, Posoquerieae, Retiniphyleae, Sipaneeae, and Steenisia. Five new tribes are here recognized (Airospermeae, Augusteae, Scyphiphoreae, Steenisieae and Trailliaedoxeae). Secondary pollen presentation, corolla aestivation patterns,fruit types, and number of ovules are all characters that have been considered of great importance in the classification of Rubiaceae. Ancestral state reconstructions of these characters using likelihood optimization indicate that secondary pollen presentation is synapomorphic for a clade comprising the Ixoroideae crown group and Retiniphyllum, whereas left-contorted corolla aestivation is synapomorphic for a clade comprising the crown group, Retiniphyllum, and Steenisia. Capsular fruits with numerous seeds are plesiomorphic in Ixoroideae, from which dry or fleshy indehiscent fruits have evolved numerous times independently. Reductions in seed number appears to have occurred within several lineages, none of which show a secondary increase in the number of seeds.

  • 48.
    Karis, Per Ola
    Stockholm University, Faculty of Science, Department of Botany.
    Tribe Arctotideae Cass.2007In: The families and genera of Vascular plants, Springer, Berlin , 2007, p. 223-229Chapter in book (Refereed)
  • 49.
    Karis, Per Ola
    et al.
    Stockholm University, Faculty of Science, Department of Botany.
    Funk, Vicki A
    Smithsonian Institution, Washington, DC 20013, USA.
    McKenzie, Robert J
    Dept of Botany, Rhodes University, Grahamstown, South Africa.
    Barker, NP
    Dept of Botany, Rhodes University, Grahamstown, South Africa.
    Chan, Raymund
    Universiti Teknologi Malaysia, Johor, Malaysia.
    Arctotideae2009In: Systematics, Evolution and Biogeography of Compositae / [ed] Funk VA, Susanna A, Stuessy TF, Bayer RJ, Vienna: International Association for Plant Taxonomy , 2009, p. 285-310Chapter in book (Other academic)
  • 50. Karpa, Daniel S.
    et al.
    Mendenhall, Chase D.
    Callaway, Elizabeth
    Frishkoff, Luke O.
    Kareiva, Peter M.
    Ehrlich, Paul R.
    Daily, Gretchen C.
    Stockholm University, Faculty of Science, Stockholm Resilience Centre. Royal Swedish Academy of Sciences, Sweden; Stanford University, USA.
    Confronting and resolving competing values behind conservation objectives2015In: Proceedings of the National Academy of Sciences of the United States of America, ISSN 0027-8424, E-ISSN 1091-6490, Vol. 112, no 35, p. 11132-11137Article in journal (Refereed)
    Abstract [en]

    Diverse motivations for preserving nature both inspire and hinder its conservation. Optimal conservation strategies may differ radically depending on the objective. For example, creating nature reserves may prevent extinctions through protecting severely threatened species, whereas incentivizing farmland hedgerows may benefit people through bolstering pest-eating or pollinating species. Win-win interventions that satisfy multiple objectives are alluring, but can also be elusive. To achieve better outcomes, we developed and implemented a practical typology of nature conservation framed around seven common conservation objectives. Using an intensively studied bird assemblage in southern Costa Rica as a case study, we applied the typology in the context of biodiversity's most pervasive threat: habitat conversion. We found that rural habitats in a varied tropical landscape, comprising small farms, villages, forest fragments, and forest reserves, provided biodiversity-driven processes that benefit people, such as pollination, seed dispersal, and pest consumption. However, species valued for their rarity, endemism, and evolutionary distinctness declined in farmland. Conserving tropical forest on farmland increased species that international tourists value, but not species discussed in Costa Rican newspapers. Despite these observed trade-offs, our analyses also revealed promising synergies. For example, we found that maintaining forest cover surrounding farms in our study region would likely enhance most conservation objectives at minimal expense to others. Overall, our typology provides a framework for resolving the competing objectives of modern conservation.

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